The Scientific Method

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The Scientific Method
2/18/1996
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Brainstorm

• What is science?
• What skills are important to a scientist?

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Goal

• What is the scientific method?
• What does the scientific method assume?
• Does the scientific method work?
• What is not a scientific argument.

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What is science?

• Science is a tool.
• Medicine I have high cholesterol, what should I
  do?
• Take cholesterol lowering medication.
• Consult your astrologer.
• Pray to the god Baal and sacrifice a goat.

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Scientific Skills

• Observation
• Inference
• Prediction
• Hypothesis
• Measurement
• Estimate
• Analyze
• Classify
• Communicate

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Experiments

• What is the best way to learn about something?
• How would you begin?

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Variables

• Affected
• Effected
• Controlled Experiment
• Control
• Variable

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The Scientific Method

• Problem
• Hypothesis-which makes a prediction.
• Experiment
• Observe
• Conclude
• Repeat as needed.
• A successful hypothesis becomes a Scientific
  Theory.

hypothesis
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Medical Science
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Everyday Science
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Everyday Science
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Food Science

• Throwing something together ? Hypothesis
• Your grandmothers time-tested recipe ?
  Scientific Theory.

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Repeatability

• A successful theory is repeatable.
• By you.
• By anyone.
• Examples
• Chemical Reactions
• Relativity (Einstein)

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Requirements

• Objective reality
• We all see the same world.
• Constant Laws of Nature
• What happens here, happens there.
• What happened yesterday will happen tomorrow.
• The Cosmos is knowable.

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Does it work?

• Scientific Method is a tool.
• Does this tool work?
• Life expectancy
• Mortality rates
• Are there better tools?

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Recap Facts, Theories, Laws

• Facts
• What does the word Theory mean to you?
• A conjecture guess (Websters Dictionary)
• Does it mean the same to a scientist?
• A model which has been born out by repeated
  tests and observation.
• Is a Theory less than a Law?
• Evolution is just a theory, it is not a fact.
• Do Theories grow up to be Laws?
• Einsteins Theory of Relativity

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Theories

• So a theory is a highly successful hypothesis.
• All hypotheses make predictions.
• All theories make predictions.
• All theories can be tested.
• Result Any scientific theory is subject to
  change as our ability to make tests, or make
  observations of a tests results, improves with
  time.

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Non-scientific Theories

• Make no predictions
• Un-testable
• Cant be falsified

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Non-scientific Theories

• Car wont work? ? Aliens drained the battery.
• Spaghetti is bland? ? You were meant to eat bland
  food.
• Car wont work? ? Gods must be angry.
• Spaghetti is bland? ? At the instant of tasting,
  tongue is transported to alternate dimension
  where all flavors are rendered nullified. Happens
  instantaneously.

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Non-scientific Theories

• The chain of events needed for life to arise is
  too complicated to have happened by chance, a
  divine intelligence must therefore have caused
  life to arise (Intelligent Design).
• Face on Mars.

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Falsification

• A real Scientific Theory tells you what
  observations are necessary to falsify it.
• Not so proponents of
• Face on Mars
• Moon Hoax
• Intelligent Design
• Astrologers